首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   208篇
  免费   25篇
  2023年   2篇
  2022年   3篇
  2021年   10篇
  2020年   4篇
  2019年   4篇
  2018年   6篇
  2017年   4篇
  2016年   6篇
  2015年   8篇
  2014年   12篇
  2013年   9篇
  2012年   14篇
  2011年   20篇
  2010年   9篇
  2009年   6篇
  2008年   6篇
  2007年   8篇
  2006年   8篇
  2005年   9篇
  2004年   11篇
  2003年   13篇
  2002年   8篇
  2001年   1篇
  1999年   1篇
  1998年   1篇
  1996年   1篇
  1993年   1篇
  1992年   2篇
  1991年   3篇
  1990年   1篇
  1989年   1篇
  1988年   5篇
  1987年   3篇
  1986年   3篇
  1985年   2篇
  1984年   2篇
  1983年   1篇
  1981年   4篇
  1980年   2篇
  1979年   3篇
  1976年   2篇
  1973年   2篇
  1972年   2篇
  1971年   1篇
  1970年   1篇
  1968年   1篇
  1966年   4篇
  1965年   1篇
  1961年   2篇
排序方式: 共有233条查询结果,搜索用时 15 毫秒
1.
Summary Sequence divergence between the 3 long terminal repeats (LTR) of avian reticuloendotheliosis virus (REV), deletion variant proviral clone 2-20-4, and spleen necrosis virus (SNV)—proviral clones 14-44, 60, and 70—was found to involve two classes of base substitutions: low-frequency interspersed and high-frequency clustered substitutions. Clones 2-20-4 and 14-44 have diverged 4.4% owing to low-frequency substitutions. In contrast, two high-frequency substitution segments have diverged by 30% and 29%, respectively. Clustered substitutions appear to be located either within or next to tandem repeats, suggesting their introduction concomitant with sequence deletions and duplications commonly associated with such repeats. A new 19-bp tandem repeat is found in clone 2-20-4. Its sequence could have evolved from the 26-bp repeats found in the SNV clones.  相似文献   
2.
Using DNA clones, the physical distance between the linked genesnov andstr inHaemophilus influenzae was estimated. Although none of the cloned inserts contained both the markers, pJ1-8StrR 13 (insert of 18·7 kb) includedstr gene at one end and part ofnov gene at the other end of the insert. By EcoRI restriction analysis and by Southern hybridization, the distance between the two EcoRI sites, cutting at which inactivates the two genes, was estimated to be 17·7 kb. A single continuous EcoRI fragment (containing 4EcoRI sites within it) carrying both the genes intact would need to be 20·4 kb in size. These estimates were confirmed independently using different clones ofnov r andstr r alleles as probes for hybridization with BamHI-digested chromosomal DNA.  相似文献   
3.
A long-term follow-up study of rostral mesencephalic reticulotomy (RMR) for pain relief is presented. 34 patients (24 males and 10 females) were operated. Ages ranged from 18 to 65 years. The follow-up period was 1-70 months. The overall effectiveness of RMR showed good relief of pain in 23 patients (67%). The study of effectiveness of RMR according to type of pain showed good relief of pain in 5 out of 6 patients (83%) with nondenervation pain, whereas satisfactory pain relief was obtained in 18 out of 28 patients (64%) with denervation pain.  相似文献   
4.
The Tolerance of Extra Chromosomes by Primitive Tomatoes   总被引:2,自引:0,他引:2       下载免费PDF全文
  相似文献   
5.
A case of somatic instability affecting aleurone colour in a strain of maize from India with flint background was analysed. The somatic instability is localized to theC 1 (Inhibitor) allele ofC locus on the short arm of chromosome 9. Molecular tests indicated thatAc is not present in the Indian stock and the evidence is consistent with the involvement of theEn (Spm) transposable element in the instability. The presence of theEn (Spm)-like element in the stock would suggest that these elements have been present in the maize genome for a long time. A new allele ofshrunken (sh1) gene with a somewhat unorthodox breeding behaviour is also described.  相似文献   
6.
Nance-Horan Syndrome (NHS) is a rare X-linked syndrome characterized by congenital cataract which leads to profound vision loss, characteristic dysmorphic features and specific dental anomalies. Microcornea, microphthalmia and mild or moderate mental retardation may accompany these features. Heterozygous females often manifest similarly but with less severe features than affected males. We describe two brothers who have the NHS phenotype and their carrier mother who had microcornea but not cataract. We identified a previously unreported frameshift mutation (c.558insA) in exon 1 of the NHS gene in these patients and their mother which is predicted to result in the incorporation of 11 aberrant amino acids prior to a stop codon (p.E186Efs11X). We also discussed genotype–phenotype correlation according to relevant literature.  相似文献   
7.

The performance of surface plasmon resonance (SPR) sensors has great dependence on its plasmonic material’s frequency response, which is described by the complex dielectric function. Through history, researchers developed and enhanced mathematical models to accurately describe the material dielectric function. Although many papers compared the accuracy of different dielectric function models and stated its limitations, none of it addressed the effect of dielectric function model on the SPR sensor’s characteristics. In this paper, we investigated the performance of the three most used dielectric function models (Drude, Lorentz-Drude, and Brendel-Bormann) and their effect on the theoretically obtained sensor parameters when used in a gold SPR sensor’s model and validated it with the experimentally measured dielectric function. The result showed that using less accurate dielectric function’s model has a drastic effect on the theoretically obtained sensor’s parameters. Among the three models, the widely used Drude model was not the most accurate; alternatively, Brendel-Bormann model was the most accurate.

  相似文献   
8.
Neurochemical Research - A selective RXR agonist, bexarotene, has been shown to have anti-inflammatory, anti-nociceptive, and neuroprotective effects in several models of numerous neurological...  相似文献   
9.
Plant Molecular Biology Reporter - Auxin plays crucial roles in modulating various aspects of plant growth and development throughout the plant life cycle. At the molecular level, auxin rapidly...  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号